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Also in this series: 1-5, 6-10, 11-15, 16-20, 21-25, 26-30, 36-40.

35. Pedro Hernandez | Starter | DOB: 4/89 | Throws: Left | Trade: White Sox

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2010     A-     29     13     4.04     100.1     122      6      79     17
2011     A+     15      6     2.70      56.2      52      3      44      6
         AA      9      8     3.48      41.1      39      4      43     10
         AAA     4      4     6.00      18.0      28      3       7      6
2012     AA     12     12     2.75      68.2      68      6      37     18
         AAA     7      6     4.46      34.1      43      2      28      4
         MLB     1      1    18.00       4.0      12      3       2      1

Pedro Hernandez was signed by the Padres out of Venezuela as a 17-year-old in 2006, traded to the White Sox as part of the package for Carlos Quentin in 2011, and acquired by the Twins along with Eduardo Escobar in the Francisco Liriano deal. He appeared in one game for the White Sox last season, getting clobbered for eight runs in four innings on July 18 against the Red Sox, and spent the rest of the year at Double-A and Triple-A.

He throws in the low-90s with more fly balls than ground balls and struggled to miss bats after advancing beyond Single-A, producing just 65 strikeouts in 103 innings last season. In the minors at least he's been able to offset all that somewhat with very good control, walking just 1.6 batters per nine innings for his career, but the left-hander has limited upside despite not yet turning 24 years old.

Hernandez has little chance to make the team out of spring training, but he has a spot on the 40-man roster and that means when the Twins need pitching reinforcements during the season he'll jump to the front of the line with any sort of decent work in Rochester. If things go well he could wind up as a useful back-of-the-rotation starter, but Hernandez struggled against right-handed hitters last year and a shift to the bullpen may be his best path to the majors.

34. Jason Wheeler | Starter | DOB: 10/90 | Throws: Left | Draft: 2011-8

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2012     A-     27     27     3.45     156.2     170     12     115     43

Jason Wheeler was a mess in his first two college seasons, but put together a solid junior year at Loyola Marymount in 2011 and was drafted by the Twins in the eighth round. He signed too late to debut, so the 6-foot-8, 250-pound left-hander began his pro career last season at low Single-A by going 14-6 with a 3.45 ERA in 27 starts. Meanwhile his brother, third base prospect and 2009 fifth-round pick Ryan Wheeler, made his MLB debut for the Diamondbacks.

Wheeler's nice-looking ERA and win-loss record overstate how well he pitched for Beloit, as he got a ton of run support from a stacked, Miguel Sano-led lineup and managed just 115 strikeouts in 157 innings. He did a decent job limiting homers, but Wheeler induced a modest number of ground balls, allowed opponents to hit .281 off him, and showed mediocre control with 2.5 walks per nine innings.

Physically he's among the largest pitchers in baseball, minors or majors, but Wheeler works in the high-80s and low-90s with his fastball. If the Twins' coaches can somehow figure out how to turn his massive frame into added velocity at age 22 he could be a breakout candidate, but short of that Wheeler looks like a potential back-of-the-rotation starter who does most things reasonably well without any standout skill.

33. Adrian Salcedo | Starter | DOB: 4/91 | Throws: Right | Sign: Dominican

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2010     RK+    16      8     3.27      66.0      55      3      65     10
         A+      6      6     6.26      27.1      42      3      16      8
2011     A-     29     20     2.93     135.0     131      4      92     27
2012     A+      8      7     6.39      25.1      33      1      14     15

In the low minors Adrian Salcedo looked like a high-upside prospect, but his stock dropped along with his strikeout rate against more experienced competition and he missed most of last season after being hit in the face by a line drive. He threw just 31 ineffective innings, wasn't picked in the Rule 5 draft after being left off the 40-man roster, and will be 22 years old by the time he throws his first pitch above Single-A.

Signed out of the Dominican Republic in 2007 as a 16-year-old, Salcedo has just 72 walks in 386 innings for a rate of 1.7 per nine frames. Brad Radke's career walk rate was 1.6 per nine innings, so for Salcedo to show that type of pinpoint control so early in his career is extremely impressive. Unfortunately his strikeouts per nine innings fell from 8.6 in rookie-ball to 6.1 at low Single-A to 5.1 at high Single-A, where Salcedo has a 6.32 ERA in 53 innings.

Salcedo's low-90s fastball and overall raw stuff have always gotten positive reviews, but even before the injury the 6-foot-4 right-hander was trending in the wrong direction. Being a control artist in the majors is one thing, but most successful low-strikeout, low-walk starters actually managed decent strikeout rates in the minors. He's still young enough to bounce back from the lost year of development time, but Salcedo's status as a quality prospect is shaky.

32. Tyler Robertson | Reliever | DOB: 12/87 | Throws: Left | Draft: 2006-3

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2010     AA     27     27     5.41     144.2     181     17      91     57
2011     AA     55      0     3.61      89.2      87      6      88     29
2012     AAA    33      0     3.77      28.2      26      2      33     13
         MLB    40      0     5.40      25.0      21      4      26     14

Once upon a time Tyler Robertson ranked among the Twins' best pitching prospects, but his strikeout rate deteriorated as his climbed the organizational ladder and injuries kept him from maintaining peak velocity. After an ugly 2010 season at Double-A the Twins decided they'd seen enough of Robertson as a starter, shifting the 6-foot-5 left-hander to the bullpen. He fared well there with a 3.65 ERA and 121 strikeouts in 118 innings between Double-A and Triple-A.

That earned him a June call-up and Robertson struck out the first four big leaguers he faced, but he struggled to consistently throw strikes and finished with a 5.40 ERA in 25 innings. He actually dominated lefties with a .190 batting average and 22-to-6 strikeout-to-walk ratio, but righties hit .290 with more walks than strikeouts. His splits were similarly extreme at Triple-A, so Robertson needs to show that he can avoid being a liability against righties.

His high-80s fastball is reason for skepticism in that area, although the off-speed repertoire from his days as a starter should come in handy. If he can improve versus righties Robertson has a chance to be a ground ball-getting setup man, but if not he'll likely be limited to a southpaw specialist role. Either way, this season will be key for Robertson because at age 25 he may not get a particularly long leash.

31. Madison Boer | Starter | DOB: 12/89 | Throws: Right | Draft: 2011-2

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2011     RK+    15      0     2.60      17.1      13      1      31      2
         A-      8      0     6.75       8.0      12      0      12      1
2012     A-      5      5     3.58      27.2      26      1      20     10
         A+     22     19     6.41     111.0     147     15      66     32

Picked out of Oregon in the second round of the 2011 draft, Madison Boer posted a ridiculous 43-to-3 strikeout-to-walk ratio in his 25-inning debut that year. Unfortunately none of that carried over to his first full season, as the 6-foot-4 right-hander from Eden Prairie got knocked around for a 5.84 ERA in 139 innings between two levels of Single-A, allowing opponents to hit .309 while managing just 5.6 strikeouts per nine innings.

Boer's lack of missed bats isn't a total shock after he struck out just 74 batters in 99 innings during his final college season and Baseball America noted before the draft that his velocity fell from the mid-90s as a reliever to the low-90s as a starter. Still, there's no way a 22-year-old top-100 pick with big-time college experience should struggle that much at Single-A, particularly after toying with rookie-ball hitters.

Boer is already 23 years old, so if he continues to struggle as a starter it'll be interesting to see how long the Twins wait to shift him to the bullpen. That's certainly not a guaranteed fix, but it would allow him to focus on the fastball-slider combo that drew pre-draft praise and would likely provide a much quicker path to the majors. At this point, though, Boer simply needs to get back to pitching well again regardless of the role.

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